Step bumper vs. regular (sport/roll) bumper mounting.

[Barbecue]

Hey all.

Truck in question is '86 Silverado SWB. Currently, I've got a chrome step bumper on the truck. Will be looking to switch to the sleeker regular style ones, referred to in the LMC truck catalog as "premium chrome bumper" (I've also seen them referred to as sport or roll bumpers). I'd like to find a OE used one, seeing as parts trucks pop up from time to time around here and I'm in no rush. So I've got a question, are the brackets and mounting hardware the same between the step bumpers and regular ones? If not, what will I require to do the switch?

Thanks everyone so much in advance for your assistance.

Cheers,

BBQ