OK, try this - the
pic here shows the loom at the top, and the
one here sorta shows the 4 way at the bottom rear - I looked at the engine pile and found
this original [~1960 car engine], the rearmost wire goes direct to the plug, the single clamp on the pan is for the next plug - I remember now the double front loom goes at the threaded hole between the side mount bosses along with the plug shield - originally intended to keep the wires from chaffing on the mount because they need to go behind it [post '59], and I used that layout on my 58 which uses the front mounts as original, the wires loop along the side of the block well ..... I can't see there could be any problem with the rams horns [which I have] even if you have the crossover Y pipe, tons of clearance in there
I also poked around the stash, and did find I had some of the single wire ones, but only have the one complete set, although I could check all the engines on hand and maybe find a few pieces - most of what I have here has to get cleared out as retirement looms

Bill