Thin SBM head gasket part numbers?

MR Gasket 1121G and the MP 4120094 are the thin head gasket...

as far as holding up....got a 71 360 Dart that has run 10.30s with those head gaskets...and they have been on that engine for over 5 yrs now...

ttps://www.monicattichrysler.com/comersus/store/comersus_viewItem.asp?idProduct=247

http://www.summitracing.com/parts/mrg-1121g