not really u can use any b15 sentra to swap a sr20ve(same car
no need for an 01 se sub frame) for the qr25de 6sp trans just need to put the sr20ve 6sp bell housing and the motor bolts up to it(transmission) use the same tranny mount, use a b15 sr20 crossmember and just make a custom passenger mount and a b13 wiring harness and ecu which does not have any NATS. it sound easy but it really takes time and patient and always good to have professional help(sr20 knowledge)