LT230S valve spring seat washers missing?
 

I'm restoring a 88 LT230S and while in the parts microfiche I noticed that there are valve spring seat washers shown, however I didn't seem to have them during rebuilding of cylinder head. It doesn't seem anybody has ever disassembled this engine before and I don't see them in any of my parts piles. Has anybody else noticed some with and some without before? They are available from Suzuki and it would't take but a hot second to remove the springs and install them. Are they absolutely necessary? I know many if not most engines have them.