On my 81 I used the hose listed for the 305 from the factory and I think I cut some off but it worked great.
2006 Superior Blue Trailblazer SS AWD, Stock as a rock
Sold: 2002 GMC Sportside Denali front end with a 2002 LS1, FLT level 5, Yank 2600, Trick Turbo, T76, Nelson intercooler, 60LB injectors, Warbro fuel pump, Eaton locker, Magnaflow, 3.42, Nelson Performance Tuning (speed density).
Sold: 1981 GMC LB RC 1500 2002 4.8L 4L60E 12 bolt 3.73 Richmond Lock Right AC PS Nelson Performance tuning
Thanks everyone for the information. Coat hanger is a great idea. And I can match it againist the hose GMCwantsLS1 mentioned. I have posted a few photos in my album. Should be ready for the cab and sheet metal soon.