When researching my keezer build I found a number of posts here and elsewhere about the threads on Perlick taps not lining up with threads on non-Perlick standard shanks. Most problems seemed to be tolerance issues when the Perlicks were mated to chrome plated shanks. Remedies most often included files, wrenching, or new shanks. Others on the other hand report no problems.
I ended up going with Perlick SS shanks. Everything went together as it should have...no leaks. You're best bet is just going to be getting a Perlick and seeing how it all fits. Best wishes.