Kindle is definitely not the right reader for someone interested in technical material. Almost any other device would be better, unfortunately.
PDFLRF is a great tool, but it'll add an extra step, since you'll need to convert the LRF to Mobi afterwards. You might want to try a similar tool, PDFRead, with .PRC output:
https://www.mobileread.com/forums/showthread.php?t=21906