Please Bring back the Ability to alter receivers

It was a very useful feature of MWII as it meant if you wanted to use a tracer weapon but wasn’t that big a fan of the base blueprint model you could alter it to one you enjoyed, I haven’t a clue why it was removed but I really want it back. As well although so far there aren’t any blueprints that use different variants of the same weapons I do hope the barrel or stock options can be used between different types like the Striker and Striker 9 as so far it can’t be done with the Ak variants and the SVA 545.