no problem as long as you will not brick your PSP 3000. I bricked my uncle's TA-088v3 PSP 2006 so Im very careful with these PSPs.
if you are already in custom firmware, DO NOT RUN the program I linked. First, if you check your motherboard, it will freeze resulting in reboot and you're back to OFW 5.03 again
you can use PSPident to check your motherboard. it's first used when installing CFW on PSP.
Like I said, yours will be TA-090v2 so need to know what your motherboard is.