Do them in groups with other players and avoid any bases with ships patrolling. Still takes a bit of time but these bases are good:
https://forums.frontier.co.uk/showt...List-and-Guide-for-Modified-Embedded-Firmware
Drop far out, kill defence turrets, kill skimmers. Work out layout and bring up map. Scan all datapoints then evac the area.
Does take a bit of time but with 2 or 3 SRV's you can mop up a base in 15 minutes or so. Back when I was after CIF and MEF I spent my Saturday evening doing bases and the rest of the week doing other things. When alone every base was about 30 minutes + travel time so I got through maybe 5 each Sat afternoon. After 2 weeks I cashed in the 30 and got good enough rolls on what I needed.
I feel for PvP if I properly put my mind to it I could get through 30-40 bases a week or 120 of whatever data I need. Considering you only get the good upgrade once and it's valid forever I think it's ok. It's a one time grind like ranks and as above it's a reliable source. The RNG of stuff like wake scans is what drives me insane, provided I know there is a reward at the end of what i'm doing its fine, but not having a confirmed place to go or direction to head in, thats what I think needs changing.
Either way said my piece here and am going to bow out of the conversation. Don't want to tread over the same ground too many times
Me thinks there is your problem. I'd bet there is nobody in the game that has a combat T7


Edit: In any case given we can swap drives around you probably only need about 5 thrusters modified right and interchange as required. Class 3 enhanced for the small ships, Class 4 for the FDL and similar, Class 5 for the FAS and similar, Class 7 for the Vette and Class 8 for the Cutter.
Even if you need 100 rolls per engine thats 500 and at 120 a week with the base assault method as above you'll be there in a month. Or in your case with 200 in the bank already you'll be there in 2-3 weeks.
Anyway yeah engineered stuff are supposed to be rare in the lore. I doubt the arguement that you want a combat everything will convince Frontier to up the drop rates. Stick to doing a few ships really well and have the others as above average instead of shooting for the magic number on everything.