Frame question

[fast&low]

Hi guy's
I just bought a 69 C10 SWB fleetside pretty much stock other than having front & rear roll pans & it's not ugly but it's not me I guess I'm just old school & love the bumper look on these trucks so I looked under it to see what I need to do to remove the roll pans & WoW the PO or the guy he paid to install them cut the front frame rail tips to install them :/
Well now I'm in search of a frame so that I can be able to bolt the front bumpers back on.
So I was wondering if the frames on these trucks are the same from 67-71?
Just good to know because SWB frames are hard to fined & probably even more so by looking for only 69 SWB frames.
Thank you for your time