specific endgame book?

Its been a long time since I"ve read spilmans book just remember it being somewhat simplistic. (I could very well be wrong? ) . I have dvoretskys and its very good but just a touch over my level. I understand it but you need to be good at a touch lower level.

I have nunns understanding chess endgames and that is excellent and covers many aspects I failed to  learn while younger.

I have nunns chess endings volume 2 rook endings (I have a lot of fun with those). I could never understand this book without the other nunn book mentioned. Many important aspects with nunns chess endgames are needed for volume 1 and 2. (He states that himself.)  He also states that he skips a lot of basic ending principles (In the understanding chess endings book.) but hits broader important principles. An excellent book and have learned a lot

Question: I know the basic principles of endings I think. So can't afford to waste $ on a book thats too simple or unneeded. However books to understand all  of dvoretskys principles would be nice to have. I had muellers dvd video on rook endames was expensive but learned and forgot a lot of what he said. Took a lot of time learned a lot but also learned there is more to be learned.

Any ideas on how to proceed without breaking the budget. Or maybe I have to? 

An excellent intermediate book is Rate Your Endgame. It's a compilation of guess the moves endgame exercises, with some practical theory thrown in.

I"ll check it out. thanks

Man you have technical endgame book, why not try strategic endgame books. Strategic endgame and technical endgame are different. For strategic endgame book I suggest, Secrets of Endgame Strategy or How To Play Chess Endgames by Muller.