It really doesn't matter which way round the intonation screws go. The original Gibson ABR-1 T-O-M bridge ones were normally set facing forwards as they sat near the top of the bridge and could get in the way of the string running unobstructed down to the stop tailpiece. Being near the top of the bridge, they were fairly easy to access over the top of the bridge pickup.

When the deeper Nashville style T-O-M bridge was introduces, the (now captive) intonation screws sat further down the bridge body so were harder to adjust if facing forwards, and being lower meant they didn't foul the strings if facing the rear, So they are normally set up with the screw facing the rear. But it's really all about ease of access to the screw.

Looking at your picture, you look like you'll be better off with the screws facing forwards as the stings pull down quite severely. I'd really think about fitting a bridge with roller saddles. I've got one on a Flying V with a Maestro-style trem, and as long as the rollers are oiled occasionally, that stays in tune very well.

It does rather look like the kit controls are higher up on the body than on a real SG, limiting the Bigsby location. Unless you abandoned the flame top and went for a solid paint colour, then there isn't a viable option for filling the existing control holes and redrilling them further down.