#1
In my other thread I said I have $600 for a guitar/amp, but I already have a bass half stack... If I buy a better guitar and a distortion pedal, instead of getting a cheaper guitar and amp, would it sound as good as a guitar amp? and would it do any damage to my bass amp?
#2
you have a yamaha? upgrade. you'll be fine with a bass head.

think about it, carlos santana used a bassman at woodstock.
#3
It won't sound good at all. Bassman amps are the odd rareity. And even now modern bassman amps are made for guitar not bass. I'd buy a guitar amp if I were you.
MM Stingray
MIA P Bass
MIM Jazz Bass
GK 700RB-II Head
GK 410SBX Cab
Sansamp 3 Ch. DI
Crybaby Bass Wah
Bass Big Muff
DD3 Delay

MIA Strat
Nashville Tele
Martin 00015M
Hot Rod Deluxe
Big Muff
DS1
Hendrix Crybaby Wah