I agree, mount some step tubes and paint the frame a semi gloss black and it'll blend in behind the tube. That height looks really good where you have it.
Did that steering wheel bolt in? A quick side by side of my square-bod gm column versus gmt-800 column says the is very similar & very close to same distance from the wheel. Its a bit different in length beyond that but thats the easier part to change/accomodate. Is it the same situation on the 67-72 gm truck column?
Started the frame chop by unbolting the trans crossmember. Burning out the rivets for the torsion bar cross member. Cutting the exhaust, fuel and brake lines.