I don't see your other comment but unfortunately the 3G Prelude B-series stuff is completely different than the "regular" B-series parts found on other Hondas. You would need a new hydraulic transmission for the B20b. The stock engine harness could be modified to work with the B20b but the easiest thing to do is just have one made by wire-worx.com. You could also ask Anthony at MotiveForcePerformance.com, he may be able to modify your harness for less. Here is some info from the swap instructions. For the full instructions contact Sean at 1funryd.com, he sells the swap mounts. These are the major things you will need: For engine/transmission: Any VTEC and non-VTEC block/head combo. B20b, B20z, B16a, B17, B18a, B18b, B18c, etc. 94-01 Integra or 99-00 Civic SI hydraulic transmissions only. No cable transmissions or weird stuff from the AWD Integra or CRV. Shifter & Linkage: Needs to be from a 94-01 Integra. The Civic SI stuff may work as well but it is not tested. The shifter linkages will need to be lengthened and an adapter plate is recommended to bolt them onto the chassis. It is also possible for you to drill new holes near the shifter and skip using the adapter plate. For axles: 90-91 Prelude (Large hubs): Use 98-01 JDM Integra Type-R axles (They must be from the JDM Type-R, because the USDM Type-R uses the smaller 88-89 style splines. Alternatively you can get regular Integra axles and just swap the outer CV joint from your 90-91 Prelude axles onto the Integra axles.) 90-91 Additional: The following axles *should* fit according to listed lengths, but are not yet tested: Right: 90-93 Accord, 97-01 Prelude Type-SH* Left: 97-01 Prelude*, 02-06 RSX Type-S* (NOTE: You need the RIGHT RSX Type-S axle to fit the LEFT side on the Prelude, it must have a female inner CV.) *Requires trimming or removing inner hub dust shield. Harness: Custom, Wireworx, or maybe MotiveForcePerformance.com

Prelude3G.com Would it just be easier to fix the head gasket on my B20A? I heard they aren't very reliable hence me considering the swap.

Yeah much easier, they are as reliable as any Honda engine. The reason most people will swap is to have an engine with more base power and/or better aftermarket support. If you aren't trying to go faster it's probably better to stick with a 3G Prelude engine.