Hey Eric,
Most Scale projects start by determining the length, width, Tunnel width, hull depth , and after plane length of a given model hull, then referring to a Master Hull Roster (MHR) available on-line at:
http://www.namba.com/content/library/scale/namba_mhr.pdf to ensure the model dimensions fit within those 1/8th Scale measurement ranges.
To ensure that you comply with your areas Sanctioning organization - IMPBA or NAMBA - check their Rule Books available on line. Normally R/C Unlimited Rule Book is more specific than either sanctioning activity, so if you intend to race in the Pacific North West. Check their rule book also for additional specifics.
Pickle Fork Depth is not a principle dimension as listed in the (NAMBA) rule book.
IMPBA rule book specifies: " All boats to be built to a scale of 1 1/2" to 1' 0" (1/8 scale) plus or minus 10% of the beam and 5% of the length listed in the APBA Master Hull Roster.
Your hull has an unusual characteristic of the deck overhanging the rear of the sponson non trip where it meets the deck.
The Master Hull Roster (MHR) hull numbers for the hulls you mentioned are: '77 -'81 Atlas Van Lines is 7701, and the '76 -'77 Bud is 7612. PAY 'n PAK and Madison this hull may fit are 7325.
Have a look at the MHR. There are plenty of people in this Scale and Sport Forum that will be glad to answer any additional questions you have. CHEERS !!! Bob