Header/Oil Filter Issues.....

Ok Guys.....see if you can help me a bit.....I just installed a set of Hedmen Headers that are pretty Old....they are a slip fit set from the 70's and are 1 5/8 tubes that look to be very nice. I have just the right side on at the moment on my 318 in my 75 Scamp and now I cannot install an oil filter on the girl.
I know that they sell 90 degree offset filter adapters, but it appears that even this will not fit in that tight little area. What I'm wanting to know, can you folks tell me if it will fit, or do I need to go with an "external" oil filter system?
At this point I'm not sure which way to go, or to just remove the headers and put the old exhaust manifolds back on.

DEWSKY