You may also remove a short length of the threaded tube that the filter screws onto, maybe 1/4" - 3/8". All that is required is enough length to fully engage all the threads in the filter body when it is tightened down, any additional length is unnecessary. This small amount helped my installation.
There are several various lengths of filters available. Use the longest one that can be made to fit.
There is also a filter adapter used on 460 engines in some truck applications that screws on in place of the filter and allows the filter to screw on at an angle of about 30 degrees, I used it at one time with success.
Like this:
http://cgi.ebay.com/ebaymotors/Ford-...spagenameZWDVW