G'day Nolan,
SuperDooper's rundown on finding the correct Illustrated Parts List [IPL] is an excellent start. Here's an alternative Briggs webpage for finding them;
http://bsintek.basco.com/MDEXResultsPages/default.aspxAnd a link to the exact IPL [PDF download] for the numbers you give:
http://bsintek.basco.com/MDEXResultsPages/PDFDisplayPage.aspx?fileName=Z6hmvAVJ1DajIIt's necessary to be careful when reading the numbers of a Quantum; the Model Number often has an uppercase letter in it. And that Code looks to have one digit too many, to me. The standard Briggs code format is YYMMDDxx.
Although they are all 190cc/12ci side valve engines, the 12 series Quantums [first model only was 10ci] came out with horsepower ratings from 4.0 to 6.5, before Briggs went to rating by torque output. If it still has a model sticker on the cowling, that may give us a lead on the rating for that particular engine; e.g. the XTS50 is rated at 5hp, the XTS60 at 6hp and so on.
Part number supersessions [i.e. where a part number has changed during the model run] are shown in the IPL, usually by Code.
Here's an example:
![[Linked Image]](https://www.outdoorking-forum.com.au/forum/uploads/usergals/2016/08/full-5630-29679-briggs_supersession_example.png)
As SD says, where different parts/assemblies, e.g. carbies, are fitted to differing Type Numbers, this will also be noted in the IPL.
With gaskets, these will be shown clearly in the IPL, so you just have to compare the pic with the old gasket. That said, it's very rare for gasket shapes to change within a model run.
+1 to Norm here - pics are very helpful.