Walter GSP 22lr upper/Conversion Kit

Is this a plug and play affair. I was thinking about getting a GSP and getting an additional upper for EIC and International. Are the uppers interchangeable or does reliability depend on the lower when you switch uppers?

Greetings,

Generally, the top ends interchange with the lower with little problem.

I did have one upper that I could not lock with the lever on the left side.

I have access to a machine shop and removed about 0.005" of metal from the upper locking lug face. Now the upper fits all GSP's I have access to.

Probably a very remote problem. Walther is very good at machining close tolerance parts.

Cheers,

Dave