I have tried the hose in the vise thing, but don't like it as it can damage the hose internally......I like to clamp the fitting in the vise and then with plenty of lube & warmth...do the hand stand bit. It was really easier because the fitting cannot move and pushing the hose compresses it in length thereby increasing the inside diameter slightly.......it works for me!! chaseing a squiggly hose in a vise is not fun..... I would not use a heat gun, but maybe a 1200 watt hairdryer would be ok,,,,not burn the hose.