Nice to know a like minded lifter!
Were you able to gain significant strength (and mass too) on a veggy diet?
I started lifting weights and eating a veggie diet approx at the same time. biggest strength and mass gains happened during the first few months.
what I learned over the last few years, which might help someone with the same goals:
strength gains come the slowest, and might change drastically from time to time. for example, increase in body fat brings huge strength gains.
when the body fat % drops, so does the strength. no matter the diet. but what's the real drawback for the strength gains regarding the veggie diet:
creatine. it is quite lower in vegeterians, due to the natural source of creatine being meat. and more creatine = more strength, basically
mass gains: for the first half year my mass gains skyrocketed. that was the period when I increased my calory and protein intake. it's called "noob gains"
after that mass came more slowly, but I don't focus on it usually. I was always quite lean, naturally it's hard for me to gain any weight. veggie diet didn't help either lol.
but when I did a diet more suitable for mass, it did come, and at a surprising rate.
so - what I think is that as long as you follow some general dietary requirements (all essential amino acids, calories, all that stuff),
doesn't matter wether you eat meat or not.
also, some vegeterian foods that increase strength (short term) are spinach (and other plants containing betaine), caffeine, garlic and catethins from green tea. grapefruit gets more nutrients to the muscles.
iron and B vitamin supplements are a good addition overall, if you don't usually get enough (most vegeterians don't).
good luck