I use Gibbs on the guns when not wanting the stink or hazards of Kroil or ATF/acetone (on stock finish, etc) or able to use heat.
Gibbs Brand I'd rank it with Kroil for effectiveness, and it's great for cleaning up locks or freeing stuck nipples on sidelock MLs and on alum. IMO paraffin (canning wax) works about as good as bee's wax for heat & wick use. U-joint or ball-joint presses beat c-clamps for pressing and are more compact.
I agree that heating doesn't require hot disassembly every time. Having press tension or using air hammer helps there during or after heating cycle. Several hot/cool cycles often allow penetrants or wax to work in better once cooled. Have used a burp gun (HD, <200 cycles/min) to remove bucket pins that
weren't stuck, just rusty, when no helper was available to take side-tension off 'em.