return 1 1/2" bulkheads Can i add ABS?

[Hustler]

My 2 1 1/2" bulkheads from the retun lines inside my overflow boxes are on each side of my tank. I would like to either put threaded 45's on there or try and manifold them and tap lok lines into a fitting?
BUT my tank is all black inside and I dont want to add any white pipes on the inside.... all i can find is black abs and I was told its alot worse for chemical leeching?
my first thought was to put plugs in then drill and tap them for 3 3/4" and run tripple lok lines on each... any added head pressure will just blow back to my skimmer and thats a plus as well
Any ideas or examples of options?