I think Gohan is stronger in raw power, honestly. Yamcha wasn't much above the Saibaimen (I have him 1.1x stronger, i.e at 1,320), yet Gohan was said to be "about 1,500" at Namek. I am on the fence about Gohan receiving a Zenkai post Vegeta fight considering his injuries weren't nearly as serious as Vegeta and Goku's (the only ones stated to have been benefited from the fight) and I'd honestly just give him a power boost based on his image training with Kuririn in the spaceship.
Saibaimen - 1,200
Yamcha - 1,320
Gohan - 1,400
That's honestly what I'd go with, in which Gohan has an advantage in raw power. Dunno if such is enough against Yamcha's advantage in battle experience and skills. Could go either way.