Around here short and wide is the hot ticket, step sides, not so much. Even if it has good bones, the 67 grill will hold it back. I assume pretty solid means it has some rust issues, which will eventually require paint and body work. If so no more than $5k even with the upgrades.
As do most people... That one year only small 67 back window, and no side marker lights make it worth more for someone looking for a 67 vs a 68-72.
I always thought the 67-68 front end was the best looking and most desireable of the 67-72 trucks.