I relocated the flame trap on my 81 without doing or buying anything real special. Basically, it involved buying a length of 5/8 ID PCV hose about two+ feet long, and finding a 3-inch long scrap of 5/8 OD copper pipe at my friend's construction site. Push one end of the 5/8 ID PCV hose over the nipple on the new breather box. Smooth up the edges of the copper pipe and push it about an inch into the new hose. Then push the new flame trap over the exposed end of the copper pipe. You can relocate it wherever you want. Cost is minimal.

Don't skip testing the breather box. Shove the new hose over the nipple, take the oil filler cap off, and blow by mouth through the hose. You should be able to blow easily through the system and feel your breath come out the oil filler cap hole. Extremely simple test while the manifold is off. Much tougher with it one. The easier it is to blow through, the easier your crankcase will breathe. Let it breathe. Good luck.

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Thanks to everyone for the help, Doug C. 81 242 Brick Off Blocks, stock; 86 240, 130K
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Thanks everyone for all the information and advice, Doug C. 81 242 Brick Off Blocks, stock, B21F (non-Turbo), M46; 86 244, B230, 140k , auto.