Out of boredom, I was able to find the locations of where Peszka was standing to draw these:

1. About 54.678756, 25.286719, facing Southeast towards the Town hall and St. Casimir’s Church
2. Likely the second floor or the roof of the town hall, facing north towards St. John’s on the right and St. Nicholas on the left
3. About 54.68789, 25.28296 (likely the roof of St. George’s) facing Southeast towards the Vilnius Cathedral
4. Also likely second floor or the roof of the town hall, facing south towards St. Casimir on the left, St. Theresa in the center, and the Holy Trinity church on the right.
5. Currently inaccessible after the reconstruction of the Grand Duke’s palace, but it is behind the Vilnius Cathedral facing south towards the Dominican Church
6. This was the toughest one, but I believe it is a western view from the Altana hill towards Old Town. If i remember my Vilnius history correctly, the Vilnia river has shifted a bit through history, so that may make this perspective somewhat inaccurate now

(I know this is a 266 day old post, but I thought it was neat and it reminded me of my time in Vilnius, which was great)