I have the PC 7518 in a Bench dog lift, The 7518 is a beast with power to spare.
Here's the thing, while the motor certainly can be removed, it is a pain to get it right and then days, a week/s or month later yank it out for a project. A couple times a year isn't so bad but if you're using it off and on for whatever the removal process will quickly get old.
I'd suggest you pick the 1617 or an outright plunge, the PC 7539 is a killer dedicated plunge. Mount it under the table and use it till you can afford a dedicated router motor.
Never bite the hand that looks dirty!
The more you know the more you're worth