I Wanna Go Fast(ish) - NP200 to NP205 swap?

[77TransAm]

My truck has a 318 with a synchroed NP435 and 4.89 gears. All things considered (apart from the NP200), it ought to tolerate 70mph. I have gathered that an NP205 is a semi-simple swap that would solve the problem without having to alter the offset diffs (run through the NP205, add the parking brake from the NP200). That all sounds good in theory, but I am sure the details are more complicated… can anyone who has done this clue me in on what type of NP205 is needed and what parts are needed to make the adaptation? I have a functional NP200 in it now (thanks to Ziggy) and the remains of the one that locked up. In the process of replacing the one that locked, I found a hole in the floor that looks to have been created by a previous t-case detonation (yikes!). I’d love to solve the issue once and for all without having to mess with the axles or the trans. Thanks!