I don't normaly bother with long threads but since it is my cup of tea and there are still a few pointers you could use here are a couple not covered so far. No doubt they will be a time or two in the not too distant.
First off, using a router to cut door hinges is a skilled job. Setting it up is, at least. It requires as much knowledge as does using hand tools. Maybe more.
I have the Trend door jig but it will stay in its box until I get 4 doors or more for it. I wouldn't hesitate if it was already set up but it is new and needs fettling.
You could do the job a lot more quickly with an inch and a half chisel and a hammer but then you would never find out how to use the router.
Either way, the door has to be fitted first. This is half the job once you have the experience. The door needs to be put in the frame with packers or wedges and checked for equal spaces all around. The ideal is top and sides equal and about 2 mm - about the thickness of a 2p coin.
The bottom needs to clear your carpet. If unfitted, allow 10 or 15 mm depending on whether you are going to have underlay. Ensure all the other edges are parallel before cutting anything down. And of course check the door top to see which side the lock goes.
Once you are satisfied it fits you can measure and mark the hinge positions. 6 or 7 inches and down from the top, 8 or 9 and up from the bottom. The idea is to clear the rails (in the good old days) and to make the hinge butts look as though they are equally spaced afterwards. (An optical illusion.)
You can mark the frame and door simultaneously. Now decide how you are going to proceed.
If you have a long enough cutter, you can just rebate the length of the hinge in one run. The cutter needs to be long enough to deal with the architrave. Use a piece of wood as a fence long enough to stop the router going past the mark for the bottom hinge. Another scrap tacked above the but at a suitable distance to act as a stop for the other side will allow you to cut the rebate without gong too far.
the improvised fence needs to be 2 inches shorter for the top hinge. The scrap piece tacked onto the frame will be the same distance as used on the bottom. For a middle hinge a couple of scraps tacked to the frame will suffice.
The scrap used as a fence should still be used though. Cut into the wood deep enough to bury all but the amount of cutter you will need to actually do the work and the fence will be your depth gauge.
You will see how it all comes together if you practise on a few bits of scrap. Once you are happy that you are proficient enough, have a go on the real thing.
Personally I'd remove the architrave if it is an old frame. Or more likely if the frame is old I would just cut into the door and use the old housings cut into the frame for the previous door.
As you can see a sharp chisel is a lot quicker if you don't have things already set up. With a chisel just mark the outline of the hinge and chop the depth into the mark that runs parallel to the rebate in the frame. Two smat whacks is just about all you need.
Then going by eye, guess how much you need to take off. If the frame is a good one, chop into the side of the frame. If it is poor timber, run down the width of the hinge housing, hazing out the stuff you want removed then insert the chisel to pare it out.
Put the hinge in and check for wabble. If it is too deep you will have to pack it with a bit of hard card. Not corrugated cardboard. Cereal box or the package the hinge came in might do.
If you are happy with the depth but it wabbles, put the hinge in on edge so you can look along the frame to see what needs paring away. Practice with a few scraps will get you proficient in a morning and you should cope well with the right chisel and a steady hand in about
1/4 of an hour per hinge.If you can fit your first door in a couple of hours one way or the other, you will be doing well. Don't rush it. As with all things do it yourself (except for plumbing and electrical stuff) the aim is to have fun.